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China University (2009)

Deep-Penetrating Geochemistry : Theoretical Consideration, Methodology And Application In Desert Terrain

Wen X Q

Titre : Deep-Penetrating Geochemistry : Theoretical Consideration, Methodology And Application In Desert Terrain

Auteur : Wen X Q

Grade : Doctoral Dissertation 2009

Université : China Uniuversity

Résumé partiel
Outcropping areas have been explored by naked-eye over a thousand years and explored by geological technology over a century. The biggest possibility to find the new large ore deposits is in covered areas. Exploration for buried ore deposits has become difficult.In this background the concept of ’deep-penetrating geochemistry’ has been begun to be present. The deep-penetrating geochemistry is to find the buried ore deposits by studying the migrating mechanism and dispersion patterns of mineralization elements or associated elements from ore body to the surface, the elemental forms and distribution in the regolith and development of technology of sampling and analysis in seek for buried ore body.Desert terrains in northern China are covered by widespread regolith sediments, which mask geochemical signals from ore bodies, and are major obstacles to mineral exploration. There is a critical need to study the vertical distribution of elements in the regolith, and to determine potential mechanisms for transferring elements from the ore body upwards through regolith cover to the surface, to establish appropriate sampling media and analytical methods.At the conclusion of this migration of our predecessors on the basis of the migration mechanism of elements the paper starts with a typical choice desert area of gold, copper and uranium mine—three types of its surface soil layer over multiple tablets class samples mobile element analysis and research and found : calcium plot elements not to the majority of the "screened", the main elements of plot calcium concentration in the upper layer of weak cement layer ; pore foam cortex node under plaster layer above (10-40 cm) weakly cemented layer is the best sampling horizon ; mineralization related elements and enrichment level in the fine-grained clay and iron-manganese oxide film, the fine-ore-bearing deep is the most effective vector information . Therefore, separation and extraction of clay and fine-grained level of iron and manganese oxide film can achieve an effective search for deep concealed ore purposes.In this thesis the migration and technology have been present as followed according to the research of mineral information over ore body based former 8 machenism of transferring:Deposits itself and associated element or its mobile forms in the mineralization, including various ions, complex atoms, colloid, sub-micron, ultra-fine to nanometer metal particles. These elements can live with the mobile form of combining the bubble surface, and was carried to the surface to air currents. When them reach close to the surface, evaporation, ion diffusion, and other factors may be involved in the relocation of elements to the surface. Because gas carried the elements geochemical barrier on the surface will be unloaded down.Using three kinds of deep-penetrating geochemical methods - Fine-separation technology, the elements of mobile extraction technology and electrochemical extraction techniques, in the desert terrains on three types (gold, copper, uranium) were concealed from the regional mine scale to mine scale - to scale methods for ore body positioning. It is found that extraction of iron-manganese oxide can be delineated ore field caused by regional anomaly rapidly, economically, effectively providing clues for prospecting the uranium deposits in basin sandstone-type and surrounding basin large ore body.These discovery, geochemical exploration anomalies explaination in desert terrains and the choice of sampling granularity and establishment of migration mechanism in desert terrains is of the great significance.

Mots clés : Deep-penetrating geochemistry, Migration mechanism, Desert regolith, Au, Cu, U ore deposits

Présentation (Globethesis)

Page publiée le 8 mai 2013, mise à jour le 1er mai 2018